Fatty Acid Profiles of Biodiesel Feedstock Fats and Oils

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The Renewable Energy Group has released a free Feedstock and Biodiesel Characteristics Report, a fairly comprehensive analysis of – yep, you guessed it! – a whole bunch of animal fats and vegetable oils.

One area they analyzed was the fatty acid profiles of common fats and oils used as biodiesel feedstocks.

If you don’t know already, fatty acid chains are the long skinny carbon chains dangling from the alcohol on a fat or plant oil molecule.  In naturally occurring oils the alcohol is glycerol, and holds onto three fatty acid chains.  In biodiesel the glycerol has usually been replaced with a methanol, and connects to a single fatty acid chain.

(Note: most biodiesel brewers will have heard of free fatty acids, or FFAs.  These are fatty acids that are no longer attached to their alcohol.)

As a reference point, the cetane molecule in diesel is 16 cabons long, and is fully saturated (coated, for lack of a better word) with hydrogen.  (Of course the fossilized diesel fuel lacks the alcohol on the end.)

Okay, how to read this chart:

The first number shows how many carbons long the fatty acid is, and the second number tells how many hydrogens it’s missing (in these places the carbon double bonds to itself and the oil is considered unsaturated).  If you look, most of these natural fats and oils are 16-18 carbons long, very similar to diesel!

You can guess cold weather flow properties by how unsaturated an oil is.  Straight fully-hydrogenated chains pack together tightly, like uncooked spaghetti, and usually make a butter-like solid.  Unsaturated chains (missing some hydrogens) have kinks and bends where the carbon double bonds to itself, making a tangly mess like cooked spaghetti.  These unsaturated oils tend to flow better at cold temperatures (note: “hydrogenated” oils are unsaturated ones that have been treated to become saturated.)

Although unsaturated oils flow better, they also have slightly less power (less dense), and are less stable.  Those double bonds are more susceptible to degradation by oxidation, breaking apart and/or reconnecting into a varnish.

Veg On!

Fairbanks Biodiesel featured in Aurora Magazine.

Aurora Magazine has put out a nice little piece on Alaska biofuels.

The Fairbanks Biodiesel “co-op” is featured, as well as little on Arctic Biofuels (also in Fairbanks).

Near the end is a mention about canola as an oilseed crop in Delta.  There’s also stuff on grasses, barley and wood.  A short but well written overview for the layperson – check it out.

Veg On!

Alaska Biodiesel Night a Success!

Wow, we had over 100 people turn out to yesterday’s Alaska Biodiesel Night. Folks flew in from all over the state, and many of key biofuel folks were in the audience to help answer the tricky questions:

Hans Geier, the Delta Canola famer has solved the problems that growing Canola in Alaska has been faced with in the past, and spoke about his farm-scale oil press.

James Jensen from the Alaska Energy Authority updated us on fish-oil projects, specifically mentioning their use of antioxidants for fuel preservation, the portable rendering plant grant, and studies to determine the benefits to the environment by capturing the oil from carcasses instead of dumping them.

A fisherman (Brian Pauling, I think?) from Dillingham asked about shelf-life and stability of fish guts/oil/biodiesel, as they are trying to get a fish oil energy project off the ground.

Tim Hudson was there to testify about the National Park Service’s successes with B100, and specifically mentioned using heated fuel systems to keep B100 driving down to -38F.

And many other folks brought up great points, from “secret diesel” recipes and unheated blending proposals, to biodiesel efforts on prop airplanes.

Anthony Destafano from SEAKsolutions, flew up from Juneau and gave a great presentation on Southeast Alaska’s renewable energy potential. He focused on the fact that biodiesel can help now, and doesn’t require the years of studies and infrastructure requirements that plague many renewable energy projects.

I tried to focus on the the title of the evening. “Biodiesel: What is it? Why is it so great? How can I get it?” We covered chemistry, ASTM specs, emissions, carbon and energy balances, lubrication and oxygenation benefits to the engine, and of course, how to obtain biodiesel. Basically, with the new Ultra-Low Sulfur Diesel (ULSD), you need some kind of additive to protect your engine – biodiesel is an excellent one, and B20 blends will run in unmodified diesel engines.

We at Arctic Vegwerks are working with the biofuels community and are expecting to sell ASTM biodiesel this summer, while hoping that local producers are up and running within a year. More on this later.

Furthermore, Arctic Vegwerks is offering a series of classes and seminars on backyard biodiesel this summer. More on this soon.

The evening ended with a great networking session in the foyer, Zane Ulin and crew from Premium Biofuels Alaska were handing out flyers on the BioPro, building off of Anthony Destefano’s fleet-scale biodiesel project in Taku that he mention in his talk. Folks from UAA were handing out questionnaires for yet another biodiesel feasibility study, and Mark Goodman from Mill and Feed told me about the skyrocketing market for yellow grease. More on grease prices soon.

Thanks to the folks from “French Fries to Go” and “Greasy Rider” for the films, to all the great people who made this happen, especially Judy Stoll who helped staff the table at the last minute, and a big cheer to the Sierra Club for sponsoring the evening. We’ll do it again.

Gasoline and Vegetable Oil Blends

I’ve had a few phone calls from Alaska folks really really wanting a cheap and easy solution to running vegetable oil. Most recently was a plan to run 90% raw Canola oil, straight from the farmer’s press, which would be “treated” with 10% gasoline.

Here’s the response I wrote:

Hmmm. It’s my belief that if it were cheap and easy everyone would be doing it. My first thoughts are “There’s no such thing as a free lunch” and “You get what you pay for.”

Blending straight vegetable oil with gasoline (or diesel) and burning it directly in your diesel vehicle should be considered *very* experimental. Of course biodiesel folks often get nervous about running heated SVO, and the 2-tank heated veg folks can get skittish about running those unheated vegoil blends.

The closest I’ve gotten to blending is the time that I left my vegoil in the injection pump overnight (I forgot to purge). I did get the 81 VW pickup started at about 40 degrees – and it didn’t cause any noticeable harm to the system – but it kicked and bucked quite a bit while thick black smoke poured out until it warmed up. I try to avoid running cold oil in a cold engine.

I do know of one guy who runs unheated 100% SVO in a early 80s VW pickup down in Moose Pass (or was it Cooper Landing?). He told me he just ran it in the summer months, and it worked well for him.

For the internet fanatics, “Diesel Secret Energy” is the most famous of the blending “miracles.” They add their secret formula (mostly petroleum aromatics similar to paint thinner), some gas and some diesel, whip it up and call it good. The only person I know of in Alaska that bought the stuff, decided after he mixed it up that he wasn’t about to put it into his tank.

Blending, however, does happen successfully. Probably the most economically significant Alaskan example is the big WWII era generators out in Dutch Harbor at the Unisea fish plant. There they blend in fish oil, in a 50-50 ratio. Of course those are old, tolerant engines.

As far as passenger vehicles go, all the studies I’ve read say that unheated vegoil in an unheated engine will cause bad things: ring/cylinder varnishing, injector coking. The older 1980s studies say this happens more with blends above 20% vegetable oil.

If you’re planning on running unheated SVO or an unheated blend in an older, more tolerant engine, you just might get away with it. Be sure to test your crankcase oil, or at least change it often, as vegetable oil will polymerize and thicken your motor oil.

Needless to say, I do not recommend running unheated blends. But if you insist, tell us how it goes!

Veg On!

Biodiesel Needs Cows – Alaska Grown Fuel

A hundred miles upriver from Fairbanks, springing from the abandoned fields of the Delta Barley Project, is the site for the Delta Junction Biodiesel Pilot Plant. Hans Geier, an Alaska Cooperative Extension agent, has been farming in Delta for over a decade. Currently he is growing Canola, along with his son, for fuel. They received a $20,000 grant to create a Canola to fuel project in rural Alaska.

Delta Junction was a part of the 1970s-1980s massive state-funded project to develop agriculture in Alaska. Farmers were given government loans to buy land and equipment for Barley farming. It failed, the loans were called in and the state acquired many of the farms through defaults. Geier purchased his first quarter-section of abandoned fields in 1994 for $9,000. Then he learned how expensive it is to farm in Alaska. His farm grew throughout the 1990s, and he is now working with a 4-year rotation of Canola followed by barley, and then 2 years of nitrogen-fixing sweet clover.

There is a common misconception that the Canola grown in Alaska is not marketable because is has a green hue to the oil, instead of a crisp golden color. Geier says he has solved that problem by early planting of a Polish variety instead of the more popular Argentine varieties.

Another myth, Geier says, is that there are no Alaska registered pesticides for Canola. Also known as rapeseed, Canola is a four foot tall type of mustard that grows so fast and weedy, that on good soil it will out compete everything but lamb’s quarters.

The Canola grown in Alaska has over 50% oil. The 50 acres Geier is currently farming will provide him with 8.9 tons of oil, over 2000 gallons. What is needed is a market not only for the oil, but for the meal leftover from the pressing. Geier says “Biodiesel needs cows.” Canola meal can be used as a fed supplement for dairy cows. But, with the impending closure of Matanuska Maid, the future of the dairy industry in Alaska is troubled.

This project is still in the early stages. Their Chinese-built seed press arrived this year, but the 7.7 horsepower diesel engine wasn’t enough to press the seeds. A 12 horsepower engine is being shipped up, along with a 10kW diesel generator to power the 240v heater in the press.

Canola can be grown well in Alaska, the first oil should be pressed this fall. Next will be to test the oil and develop truly Alaska Grown fuel.

Source: personal interview, Hans Geier November 1, 2007